This bulletin applies to 2014-2016 Cadillac ELR vehicles. The technician may find DTCs P1B03, P0C01 or P0C4E set in history. The check engine light may be on, accompanied by messages “Engine Unavailable” and “Propulsion Power is Reduced.” The engine may also run rough. The most common DTC is P1B03.
Review the following when trying to diagnose a vehicle setting P1B03, P0C01 or P0C4E. Some diagnostic procedures may not comprehend the possibility of Motor 1 stator as the cause of these DTCs. If one or more of these diagnostics are set, especially on a vehicle with a lifetime fuel economy below 50 mpg and above average annual mileage, inspect the Motor 1 stator for damage. If no damage is found, replace the Motor 1 position sensor, transmission internal harness and Motor 1 stator (damage may be on windings below the top layer). Replacing the Drive Motor Generator Control Module should only be done if the condition persists after replacing these parts.
If the vehicle is not starting and is setting an active P0C17 after repair or reprogramming, this stator condition may also be present. Check the 3-phase copper ring terminal fasteners for proper torque if they were removed as part of a repair. The P0C17 indicates that the motor control processor cannot properly learn the position sensor due to a lack of proper high voltage and 3-phase current readings. If both P0C17 and P0C18 are set, a programming event on the high-speed bus is required to enable a wide position sensor learn. If a wide sensor learn does not remove the DTC, it may be possible that DC high voltage is not reaching the drive motor generator control module, which may indicate a battery contact or malfunction or disconnected high voltage cable.
